Genetic variation within and among populations of Camelliajaponica (Theaceae) in Korea

1996 ◽  
Vol 26 (4) ◽  
pp. 537-542 ◽  
Author(s):  
Myong Gi Chung ◽  
Soon Suk Kang
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Pollen Dispersal ◽  
Island Populations ◽  
Generation Times ◽  
Genetic Diversity And Structure ◽  
Stump Sprouting ◽  
Ability To Regenerate ◽  
The Mean ◽  
High Level

The genetic diversity and structure of 17 Korean populations of Camelliajaponica L., a broad-leaved evergreen tree, was examined. Although most populations are restricted to several islands near the southern and southwestern coast of the Korean Peninsula, they maintain higher levels of genetic variation within populations than do long-lived, woody angiosperms. For example, 13 of 16 loci examined were polymorphic in at least one population, the mean number of alleles per locus was 2.63, and mean expected heterozygosity was 0.265. These values were comparable with those for continuously distributed, mainland populations of C. japonica in Japan. However, a considerably high level of heterozygote deficiency was observed in Korean populations of C. japonica (mean FIS = 0.202). About 13% of the total genetic variation was found among populations (GST = 0.129). Indirect estimates of the number of migrants per generation (1.69, calculated from FST; 2.14, calculated from the mean frequency of eight private alleles) indicate that gene flow among island populations is moderate. Factors contributing to the high levels of genetic diversity found in the entire species of C. japonica include long generation times, ability to regenerate by stump sprouting, predominant outcrossing induced by animal vectors, and occasional pollen dispersal by birds.

scholarly journals Analysis of genetic diversity of Ficus carica L. (Moraceae) collection using simple sequence repeat (SSR) markers

2019 ◽  
Vol 18 (4) ◽  
pp. 93-109
Author(s):  
Ilaria Marcotuli ◽  
Andrea Mazzeo ◽  
Domenica Nigro ◽  
Stefania Lucia Giove ◽  
Angelica Giancaspro ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Ficus Carica ◽  
Accurate Information ◽  
Main Crop ◽  
Polymorphic Pattern ◽  
Genetic Diversity And Structure ◽  
The Mean ◽  
High Level ◽  
Simple Sequence ◽  
Modern Technologies

Modern technologies and accurate information on genetic diversity and structure are contributing to improve the plant breeding, in particular for all the minor species with a lack of data. Genetic diversity of 139 different Ficus carica L. genotypes collected from Italy and Croatia, and divided into two subgroups: uniferous (only main crop) and biferous (breba and main crop), was investigated using 49 microsatellite markers. A total of 70 alleles were generated, of which 64 (91.4%) showed a polymorphic pattern indicating high level of genetic diversity within the studied collection. The mean heterozygosity over the 64 single locus microsatellites was 0.33 and the expected and observed averaged variance were 16.50 and 184.08, respectively. The 139 fig genotypes formed two clusters in the PCoA analysis, suggesting a division between Italian and Croatian genotypes. Moreover, the fig accessions could be divided into two main clusters based on the STRUCTURE analysis according to the biological type, uniferous or biferous, with partly overlapping varieties. In conclusion, our results demonstrated that molecular markers were able to discriminate among genotypes and useful for the authentication of fig tree varieties (homonymies and synonymies).

High level of genetic diversity among spelt germplasm revealed by microsatellite markers

Genome ◽  
2004 ◽  
Vol 47 (6) ◽  
pp. 1043-1052 ◽  
Author(s):  
P Bertin ◽  
D Grégoire ◽  
S Massart ◽  
D de Froidmont
Keyword(s):  
Genetic Diversity ◽  
Triticum Aestivum L ◽  
Genetic Distances ◽  
Group Method ◽  
Germplasm Collections ◽  
Pair Group ◽  
Genetic Diversity And Structure ◽  
The Mean ◽  
High Level ◽  
Shared Alleles

The genetic diversity of spelt (Triticum aestivum (L.) Thell. subsp. spelta (L.) Thell.) cultivated presently is very narrow. Although the germplasm collections of spelt are extensive, the related genetic knowledge is often lacking and makes their use for genetic improvement difficult. The genetic diversity and structure of the spelt gene pool held in gene banks was determined using 19 simple sequence repeat (SSR) markers applied to 170 spelt accessions collected from 27 countries and 4 continents. The genetic distances (1 – proportion of shared alleles) were calculated and an unweighted pair-group method with arithmetic averaging (UPGMA)-based dendrogram was generated. The genetic diversity was high: 259 alleles were found and the mean interaccession genetic distance was 0.782 ± 0.141. The dendrogram demonstrated the much higher genetic diversity of spelt held in germplasm collections than in the currently used genotypes. Accessions with the same geographical origin often tended to cluster together. Those from the Middle East were isolated first. All but one of the Spanish accessions were found in a unique subcluster. Most accessions from eastern Europe clustered together, while those from northwestern Europe were divided into two subclusters. The accessions from Africa and North America were not separated from the European ones. This analysis demonstrates the extent of genetic diversity of spelts held in germplasm collections and should help to widen the genetic basis of cultivated spelt in future breeding programs.Key words: spelt, SSR, microsatellites, genetic diversity, germplasm.

scholarly journals Genetic diversity in Brazilian tall coconut populations by microsatellite markers

2013 ◽  
Vol 13 (4) ◽  
pp. 356-362 ◽  
Author(s):  
Francisco Elias Ribeiro ◽  
Luc Baudouin ◽  
Patricia Lebrun ◽  
Lázaro José Chaves ◽  
Claudio Brondani ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Microsatellite Markers ◽  
Cape Verde ◽  
Coconut Palm ◽  
Different Populations ◽  
The Mean ◽  
High Level ◽  
Brazilian Populations

The tall coconut palm was introduced in Brazil in 1553, originating from the island of Cape Verde. The aim of the present study was to evaluate the genetic diversity of ten populations of Brazilian tall coconut by 13 microsatellite markers. Samples were collected from 195 individuals of 10 different populations. A total of 68 alleles were detected, with an average of 5.23 alleles per locus. The mean expected and observed heterozygosity value was 0.459 and 0.443, respectively. The number of alleles per population ranged from 36 to 48, with a mean of 40.9 alleles. We observed the formation of two groups, the first formed by the populations of Baía Formosa, Georgino Avelino and São José do Mipibu, and the second by the populations of Japoatã, Pacatuba and Praia do Forte. These results reveal a high level of genetic diversity in the Brazilian populations.

scholarly journals Conservation genetics of the threatened plant species Physaria filiformis (Missouri bladderpod) reveals strong genetic structure and a possible cryptic species

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247586
Author(s):  
Christine E. Edwards ◽  
Brooke C. Tessier ◽  
Joel F. Swift ◽  
Burgund Bassüner ◽  
Alexander G. Linan ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Structure ◽  
Plant Species ◽  
Genetic Drift ◽  
Rare Species ◽  
Ex Situ ◽  
Ouachita Mountains ◽  
Genetic Diversity And Structure ◽  
Genetic Clusters

Understanding genetic diversity and structure in a rare species is critical for prioritizing both in situ and ex situ conservation efforts. One such rare species is Physaria filiformis (Brassicaceae), a threatened, winter annual plant species. The species has a naturally fragmented distribution, occupying three different soil types spread across four disjunct geographical locations in Missouri and Arkansas. The goals of this study were to understand: (1) whether factors associated with fragmentation and small population size (i.e., inbreeding, genetic drift or genetic bottlenecks) have reduced levels of genetic diversity, (2) how genetic variation is structured and which factors have influenced genetic structure, and (3) how much extant genetic variation of P. filiformis is currently publicly protected and the implications for the development of conservation strategies to protect its genetic diversity. Using 16 microsatellite markers, we genotyped individuals from 20 populations of P. filiformis from across its geographical range and one population of Physaria gracilis for comparison and analyzed genetic diversity and structure. Populations of P. filiformis showed comparable levels of genetic diversity to its congener, except a single population in northwest Arkansas showed evidence of a genetic bottleneck and two populations in the Ouachita Mountains of Arkansas showed lower genetic variation, consistent with genetic drift. Populations showed isolation by distance, indicating that migration is geographically limited, and analyses of genetic structure grouped individuals into seven geographically structured genetic clusters, with geographic location/spatial separation showing a strong influence on genetic structure. At least one population is protected for all genetic clusters except one in north-central Arkansas, which should therefore be prioritized for protection. Populations in the Ouachita Mountains were genetically divergent from the rest of P. filiformis; future morphological analyses are needed to identify whether it merits recognition as a new, extremely rare species.

scholarly journals Genetic Diversity and Evolutionary Relationships of Chinese Pepper Based on nrDNA Markers

Forests ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 543
Author(s):  
Shijing Feng ◽  
Jinshuang Niu ◽  
Zhenshan Liu ◽  
Lu Tian ◽  
Xiangyuan Wang ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic System ◽  
Haplotype Network ◽  
Evolutionary Relationships ◽  
Genetic Profile ◽  
Coding Region ◽  
Demographic Trends ◽  
Evolutionary Forces ◽  
High Level

Chinese pepper, referring to Zanthoxylum bungeanum Maxim. and Zanthoxylum armatum DC. species, is an important spice crop that has long attracted people’s interest due to its extensive application in Asian cuisine to improve taste. Numerous cultivars have been developed during the long history of domestication and cultivation. However, little to no information is available on the genetic diversity and evolutionary relationships of Chinese pepper cultivars and their historical diversification has not been clarified. Herein, we sequenced two nrDNA non-coding region markers, the external transcribed spacer (ETS) and the internal transcribed spacer 2 (ITS2), to assess genetic diversity and phylogenetic relationships among 39 cultivated and wild populations of Chinese pepper from eight provinces and to address the question of ancient demographic trends which were probably influenced by changing climate during evolutionary history. In total, 31 haplotypes were identified based on 101 polymorphism sites. Our results revealed relatively high level of genetic variation despite long-term cultivation of this crop. AMOVA revealed that genetic variation existed predominantly within provinces rather than among provinces. The genetic structure result based on haplotype network analysis largely reflected historical records, which suggested a Gansu origin for Chinese pepper and an ancient west-to-east spread of Chinese pepper circulating in China. We also provided evidence that changing Pleistocene climates had shaped the demographic trends of Chinese pepper. Taken together, our findings not only suggest that Chinese pepper is a dynamic genetic system that responds to evolutionary forces, but it also provides a fundamental genetic profile for the conservation and responsible exploitation of the extant germplasm of Chinese pepper and for improving the genetic basis for breeding the cultivars.

scholarly journals How diverse can rare species be on the margins of genera distribution?

AoB Plants ◽  
2019 ◽  
Vol 11 (4) ◽  
Author(s):  
Alice Backes ◽  
Geraldo Mäder ◽  
Caroline Turchetto ◽  
Ana Lúcia Segatto ◽  
Jeferson N Fregonezi ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genetic Variation ◽  
Genetic Variability ◽  
Habitat Loss ◽  
Evolutionary History ◽  
Founder Effects ◽  
Geographical Isolation ◽  
Genetic Diversity And Structure ◽  
Genetic Patterns

Abstract Different genetic patterns have been demonstrated for narrowly distributed taxa, many of them linking rarity to evolutionary history. Quite a few species in young genera are endemics and have several populations that present low variability, sometimes attributed to geographical isolation or dispersion processes. Assessing the genetic diversity and structure of such species may be important for protecting them and understanding their diversification history. In this study, we used microsatellite markers and plastid sequences to characterize the levels of genetic variation and population structure of two endemic and restricted species that grow in isolated areas on the margin of the distribution of their respective genera. Plastid and nuclear diversities were very low and weakly structured in their populations. Evolutionary scenarios for both species are compatible with open-field expansions during the Pleistocene interglacial periods and genetic variability supports founder effects to explain diversification. At present, both species are suffering from habitat loss and changes in the environment can lead these species towards extinction.

Genetic diversity in Elymus caninus as revealed by isozyme, RAPD, and microsatellite markers

Genome ◽  
1999 ◽  
Vol 42 (3) ◽  
pp. 420-431 ◽  
Author(s):  
Gen-Lou Sun ◽  
Oscar Díaz ◽  
Björn Salomon ◽  
Roland von Bothmer
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Microsatellite Markers ◽  
Correlation Coefficients ◽  
Geographic Isolation ◽  
Elymus Caninus ◽  
Distance Matrices ◽  
High Level ◽  
Mantel’S Test ◽  
Similarity Matrices

Genetic diversity of 33 Elymus caninus accessions was investigated using isozyme, RAPD, and microsatellite markers. The three assays differed in the amount of polymorphism detected. Microsatellites detected the highest polymorphism. Six microsatellite primer pairs generated a total of 74 polymorphic bands (alleles), with an average of 15.7 bands per primer pair. Three genetic similarity matrices were estimated based on band presence or absence. Genetic diversity trees (dendrograms) were derived from each marker technique, and compared using Mantel's test. The correlation coefficients were 0.204, 0.267, and 0.164 between isozyme and RAPD distance matrices, RAPD and microsatellite distance matrices, and between isozyme and microsatellite distance matrices, respectively. The three methodologies gave differing views of the amount of variation present but all showed a high level of genetic variation in E. caninus. The following points may be drawn from this study whether based on RAPD, microsatellite, or isozyme data: (i) The Icelandic populations are consistently revealed by the three dendrograms. The congruence of the discrimination of this accession group by RAPD, microsatellite, and isozyme markers suggests that geographic isolation strongly influenced the evolution of the populations; (ii) The degree of genetic variation within accessions was notably great; and (iii) The DNA-based markers will be the more useful ones in detecting genetic diversity in closely related accessions. In addition, a dendrogram, which took into account all fragments produced by isozymes, RAPDs, and microsatellites, reflected better the relationships than did dendrograms based on only one type of marker.Key words: Elymus caninus, genetic diversity, isozymes, RAPDs, microsatellites.

Conservation genetics and ecology of the endangered rainforest shrub, Triunia robusta, from the Sunshine Coast, Australia

2002 ◽  
Vol 50 (1) ◽  
pp. 93 ◽  
Author(s):  
Alison Shapcott
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Flow ◽  
Conservation Genetics ◽  
Population Size ◽  
Genetic Similarity ◽  
Small Region ◽  
Geographic Proximity ◽  
Close Proximity ◽  
The Mean

Triunia robusta, which until recently was thought to be extinct, is now classified nationally as endangered. It is an understorey species restricted to the subcoastal rainforests in a small region of the Sunshine Coast, Queensland. The project involved sampling the genetic variation and measuring the population size and size distribution of T. robusta and its geographically closest congener T. youngiana, which occurs further south and has a wider geographic distribution. A total of 877 T. robusta plants were recorded across the 11 populations, approximately half (56.8%) of these were juveniles less than 1 m tall, whereas in T. youngiana only about 36.4% of a population was composed of juveniles. Genetic diversity was similar but significantly higher for T. robusta than T. youngiana if the very small T. robusta populations (2 or 3 plants) were excluded from analysis (P < 0.05). The mean percentage of polymorphic loci among populations was high for both species. Triunia robusta is not, on average, more inbred than the more common T. youngiana. There was more differentiation between the T. robusta populations, which were in close proximity, than between the more geographically separated T. youngiana populations. Thus, there is evidence of more gene flow between populations of T. youngiana than between those of T. robusta. However, there was no geographic relationship between genetic similarity and geographic proximity in T. robusta

scholarly journals Genetic evaluation of seeds of highly endangered Pinus uliginosa Neumann from Węgliniec reserve for ex-situ conservation program

2011 ◽  
Vol 74 (3) ◽  
pp. 237-242 ◽  
Author(s):  
Andrzej Lewandowski ◽  
Jarosław Burczyk ◽  
Witold Wachowiak ◽  
Adam Boratyński ◽  
Wiesław Prus-Głowacki
Keyword(s):  
Genetic Variation ◽  
Genetic Erosion ◽  
Minimum Variance ◽  
Ex Situ ◽  
The Mean ◽  
Low Levels ◽  
Species Specific ◽  
High Level ◽  
Individual Trees ◽  
Pinus Uliginosa

Peat-bog pine <em>Pinus uliginosa</em> Neumann has become extinct or rare in many parts of Europe. We have investigated the levels of genetic variation and inbreeding in seeds collected from a highly endangered reserve of this species in Poland, using allozymes as genetic markers. Generally, a high level of genetic variation was observed. The mean expected heterozygosity was 0.376, while average (Na) and effective (Ne) numbers of alleles per locus were 2.45 and 1.67, respectively. Nevertheless, we have detected relatively low levels of outcrossing, and potential biparental inbreeding. The population-wide multilocus outcrossing rate was estimated to be 0.706 (±0.091), while the minimum variance mean of single-locus estimates was distinctly lower (ts=0.611). The estimates of outcrossing calculated for individual trees ranged widely from 0.051 to 1.017, indicating the complexity of outcrossing patterns. The investigated population of <em>P. uliginasa</em> from Węgliniec is small and surrounded by extensive forest stands of <em>P. sylvestris</em>. Our three-year records of phenological observations demonstrated that flowering periods for <em>P. uliginosa</em> and <em>P. sylvestris</em> overlap, allowing for cross-pollination. The possibility of <em>P. uliginosa</em> pollination by <em>P. sylvestris</em> creates a potential danger of genetic erosion of the <em>P. uliginosa</em> gene pool. Nonetheless, based on a species specific cpDNA marker we have found that among 533 seedlings of <em>P. uliginosa</em> there were only six seedlings carrying cpDNA marker specific for <em>P. sylvestris</em>, indicating that such hybridization seems to be rare.

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